Preliminary study of correlations between the intratumoral microvessel density and the morphological profile of colorectal carcinoma.

AIM: New blood vessel formation (angiogenesis) is a fundamental event in the process of tumor growth and metastatic dissemination. The aim was to evaluate intratumoral vascular density (ITMVD) and to analyze possible correlations between ITMVD and the morphological profile of colorectal carcinoma.

MATERIALS AND METHODS: The studied group consisted of 50 patients that underwent surgery for colorectal tumors, 12 of them receiving preoperatory radiotherapy. The analyzed morphological parameters were tumor site, tumor gross aspect, tumor longitudinal and transverse diameter, tumor grading, local invasion (pT), regional invasion (pN), distant metastases (pM) and intratumoral microvessel density (ITMVD) expressed as number of capillaries÷mm². The malignant tissue samples were included in paraffin blocks and serial tissue sections were cut both for Hematoxylin-Eosin staining and CD34 immunomarking. For each case, five consecutive fields without necrosis were randomly selected with ×10 objective. Quantitative measurements were performed using special software for image analysis.

RESULTS: For non-irradiated colorectal tumors, ITMVD was the highest in rectal localization, in infiltrative tumors, in circumferential tumors, in tumors with low longitudinal extension, in moderately differentiated (G2) tumors and in pT4, pN0 and pM1 tumors.

DISCUSSION: Correlations showed different trends of ITMVD depending on each parameter: ITMVD was higher when the tumor was closer to the rectum, when it was more infiltrative, more circumferential or with low longitudinal diameter. These trends might be exploited in defining future anti-angiogenic therapeutic strategies.

CONCLUSIONS: There were some interesting correlations between ITMVD and studied morphological parameters that have to be validated on larger series of cases.